The invention relates to a magnetic tape drive arrangement without pressure roller, which arrangement comprises a capstan,
a capstan drive motor, PA1 a magnetic tape transport device for supplying and taking up a magnetic tape under tension along the capstan by means of at least one winding motor, PA1 an energizing circuit, connected to the capstan motor, for driving the magnetic tape with the desired speed by means of the capstan, PA1 a control signal generator for controlling at least the winding motor in such a way that the magnetic tape can be driven by the capstan without the tape slipping past the capstan, and PA1 a motor current detector, which is connected to the control signal generator for detecting the current consumed by the capstan drive motor and for supplying a signal, which is proportional to said motor current, to the control signal generator.
Such a magnetic tape drive arrangement may inter alia be employed in audio and video tape recorders and is known from U.S. Pat. No. 3,807,654. This Patent states that, in order to prevent the tape from slipping past the capstan in a drive system without pressure rollers, the magnetic tape transport device should be controlled so that the capstan drive motor need not perform any work, the current consumption of the capstan drive motor being used as a control signal.
However, in this known arrangement very stringent requirements must be imposed on the friction between capstan and magnetic tape in order to prevent slip.